Halogen Gas Cleaning of MoFx Deposits in Semiconductor Tools
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The production of semiconductor devices faces challenges with impurities such as molybdenum monofluoride to molybdenum pentafluoride (MoFx) and their oxides accumulating as deposits or coatings in production apparatuses, leading to decreased purity, clogging, and contamination issues during chemical vapor deposition and etching processes.
Innovation Solution
A method involving the use of a halogen-containing gas, specifically a fluorine-containing gas with a bond energy between 1.7 eV and 2.5 eV, is brought into contact with the deposits or coatings to oxidize and remove MoFx and MoOFx from the apparatus surfaces, preventing clogging and contamination.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If MoF6 is used as a raw material for depositing molybdenum metal by CVD or as an etching material, then semiconductor device production is enabled, but impurities such as MoFx and MoOFx accumulate as deposits or coatings in the production apparatus, causing clogging and contamination
Solution Approach 1:
The patent applies preliminary action by introducing a halogen-containing gas into the production apparatus before the actual CVD or etching process to prevent deposit accumulation. The halogen-containing gas reacts with potential MoFx impurities in advance, converting them into volatile compounds that can be easily removed, thereby preventing clogging and contamination before they affect productivity
Solution Approach 2:
The patent uses a halogen-containing gas as an intermediary substance to resolve the contradiction between productivity and deposit accumulation. The halogen-containing gas acts as a mediator that reacts with MoFx impurities, transforming them into removable compounds, thus enabling continuous high-productivity operation without clogging or contamination of the production apparatus
2Ease of manufacture
If MoFx impurities are present in MoF6, then the raw material can be used for CVD and etching processes, but the purity of MoF6 decreases and maintenance of the reaction device becomes difficult
Solution Approach 1:
The patent applies parameter changes by introducing a halogen-containing gas that changes the chemical state of MoFx impurities. The halogen-containing gas reacts with MoFx to form volatile compounds with different physical and chemical parameters, enabling easy removal of impurities and restoration of MoF6 purity while maintaining the ease of manufacture for CVD and etching processes
3Reliability
If deposits of MoFx and MoOFx are removed from the production apparatus, then clogging and contamination are avoided, but additional processing steps and time are required
Solution Approach 1:
The patent applies preliminary action by performing deposit prevention through halogen-containing gas treatment during or before the production process, rather than requiring separate removal steps afterward. This preliminary intervention maintains apparatus integrity while minimizing additional time requirements, as the prevention mechanism operates concurrently with or prior to the main production activities
Solution Approach 2:
The patent implements self-service by enabling the production apparatus to automatically handle deposit removal through the halogen-containing gas mechanism. The system uses its own operational resources (the halogen-containing gas already present in the process) to eliminate deposits, maintaining apparatus integrity without requiring external maintenance interventions or additional time for separate cleaning operations
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This method effectively removes MoFx and MoOFx impurities, ensuring stable semiconductor device production by preventing apparatus clogging and contamination, thereby maintaining apparatus integrity and purity.
Implementation Method 1
bringing a halogen-containing gas into contact with a member having a deposit or a coating of MoFx or MoFx and MoOFx; and removing MoFx or MoFx and MoOFx from the member
Data Source
AI summary
The present invention relates to a method for removing MoFx or MoFx and MoOFx, including: bringing a halogen-containing gas into contact with a member having a deposit or a coating of MoFx or MoFx and MoOFx (where x represents a number greater than 0 and less than 6); and removing MoFx or MoFx and MoOFx from the member, a method for removing a deposit or a coating from a member having the deposit or the coating of MoFx or MoFx and MoOFx mixed as impurities in MoF6 by a method for producing a semiconductor device including the above removing method, and a method for producing a semiconductor device that includes removing a deposit or a coating from a semiconductor device production apparatus having a deposit or coating of MoFx or MoFx and MoOFx, and that can avoid clogging or contamination of the production apparatus.